Description
In Bouncy Castle for Java before 1.85, Name Constraints bypass via trailing dot in rfc822Name and URI. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2 (2.0.X series) and 2.1.3 (2.1.X series).
Affected products
bouncycastle: bc-java; bouncycastle: bouncy castle for java lts; bouncycastle: fips java api
References2
- github.com/bcgit/bc-java/commit/2c28b253a44681fbbc562561eab6ad3… Patch
- github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%908763 Third Party AdvisoryPatch
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Amber - EPSS — exploit probability
- 0% percentile: 38 · as of 13 November 2026
- CWE
- CWE-295
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